1: (0 5 15)

(0)(1 20 6)(2 16 4)(3 8 5 18 15)(7 11 9)(10 14 12)(13 19 17)

2: (1 20 6)

(0)(1)(2 16 4)(3 8 5 18 15)(6)(7 11 9)(10 14 12)(13 19 17)(20)

3: (5 18 8)

(0)(1)(2 16 4)(3 8 15)(5)(6)(7 11 9)(10 14 12)(13 19 17)(18)(20)

4: (13 19 17)

(0)(1)(2 16 4)(3 8 15)(5)(6)(7 11 9)(10 14 12)(13)(17)(18)(19)(20)